Hewlett-packard Company

Hewlett-packard Development Company, L.P.

Allen L Frazier

Jan Philip Allebach

David J Arcaro

Wayne E Foote

Brent Michael Bradburn

Kenneth A Lindblom

The data required to specify an image which is to be printed by a printing device, such as an ink-jet or laser printer, can be substantially reduced by omitting the data specifying the dot size or amplitude modulation (AM). Instead, the processor of the printing device determines the dot density in the immediate vicinity of each dot and, from that density measurement, calculates the appropriate dot size and modulates the dot size accordingly when driving the print head or print laser.

Image printing devices with AM/FM half-toning with self-determination of dot size and method of implementing same

In a device including a replaceable cartridge containing a consumable material, the cartridge having at least one moving part, a system for estimating the use of consumable material from the cartridge is disclosed. The system includes an information storage medium secured to the moving part of the cartridge. A read-write head is mounted in the device in proximity with the information storage medium, and is adapted and constructed to write information on and read information from the information storage medium. The storage medium can be provided as a magnetic storage medium, which may be configured as an annular disc. The moving part can be provided as a generally cylindrical roller assembly including a drive gear. The drive gear can include an end surface to which the storage medium may be secured. The device itself can be any suitable printing device, such as a laser printer. The cartridge may be provided as a toner cartridge, in which instance the consumable material would be toner. In an embodiment, the storage medium may be secured to an Organic Photo Conductor ('OPC') roller. A method for estimating the use of consumable material from the cartridge is also disclosed, in which the read/write head is actuated to write cartridge use information on and read cartridge use information from the information storage medium in response to operation of the device.

Method and apparatus for toner level monitoring and motion sensing

Image data such as text or half-tone images is compressed and decompressed. A compressor has three phases: a bit-run length phase that counts the length of each run of consecutive identical pixels; a pairs-repetition phase that compresses repeated pairs of pixel run values to one copy of the repeated pair and a repeat count; and an optional dictionary-based micro-table encoder. The micro-table, which may be used in any application calling for a least recently used (LRU) mechanism, has multiple qualification layers, with elements within a qualification layer being promoted to the next higher qualification layer upon the occurrence of a table hit for that element, and being demoted to the next lower qualification layer by being bumped by elements promoted up from below. The result is a table that is weighted both by frequency and recency of hits.

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Eagle, ID, United States of America

Allen L Frazier